Technical Field
[0001] The present invention relates to an extremely small diameter endoscope, and specifically
to an extremely small diameter endoscope for inspecting and imaging the interior of
the root canal of a tooth or the interior of a periodontal pocket.
Background Art
[0002] In the field of dental treatment, it is most important to understand the shape and
condition of the interior of a root canal in the case of endodontic treatment and
understand the shape and condition of the interior of a periodontal pocket in the
case of periodontal disease treatment, in order to diagnose the presence or absence
of source of infection from contaminants such as bacterium, which is a pathologic
cause, or in order to diagnose a tooth root fracture or the like. In addition, it
is also most important to remove contaminants as much as possible. However, in some
circumstances, such important therapeutic treatments are performed blindly especially
in endodontic treatments. In recent years, surgical microscopes have begun to be widely
used and observation of the interior of a root canal has become easier than before.
However, the root canal often curves as it extends, and may have a blind spot that
cannot be observed using those surgical microscopes.
[0003] An example of this type of root canal imaging instrument is the intraoral scope proposed
in Patent Literature 1. This intraoral scope includes a hand piece and a chip insertably
connected to the hand piece in an attachable and detachable manner. The hand piece
has a light source and the chip has a light guide and an image guide. The light guide
receives light from the light source and guides the received light to a distal end
of the chip to emit the light forward from the distal end. The image guide transmits
an image of a portion irradiated with the light from the light guide. The hand piece
further has imaging means for capturing the image transmitted via the image guide.
The chip is constituted by a guide tube through which the light guide and the image
guide are inserted. A distal end of the guide tube is inserted into a desired portion
inside a root canal to transmit an image ahead of the light guide via the image guide
to the hand piece. The instrument further has an attachment that is attached to the
distal end portion of the chip in an attachable and detachable manner and is adapted
for insertion into a periodontal pocket (gap between a tooth and gum). The attachment
has extended portions extending forward in parallel with each other and interposing
the guide tube in between. Each of the extended portions has a thickness in a height
direction that decreases as it extends forward.
[0004] The intraoral scope of Patent Literature 1 is mostly used for observing images of
the interior of a periodontal pocket. Moreover, the chip has a complicated structure
as follows: the chip is constructed with the guide tube through which the light guide
and the image guide are inserted and is provided with an attachment attached to a
distal end portion of the chip in an attachable and detachable manner, which attachment
is for insertion into a periodontal pocket and has extended portions whose distal
end portions each have a gradually decreasing dimension as it extends forward. In
addition, the chip does not have a configuration for preventing damages to an endoscope
insertion part.
[0005] That is, currently, there is no such extremely small diameter endoscope that allows:
inserting/removing a distal end portion of an endoscope insertion part with an extremely
small-diameter for capturing images into/from the interior of the root canal of a
tooth or the interior of a periodontal pocket with good operability; capturing images
of the interior, including blind spots thereof, of the root canal or the periodontal
pocket; and preventing the distal end portion of the endoscope insertion part from
being damaged while it is not being used.
Prior Art Documents
Patent Literatures
[0006] Patent Literature 1: Patent No.
5391019
Summary of the Invention
Problems to be Solved by the Invention
[0007] The present invention has been made in view of the above-described circumstances.
The present invention provides an extremely small diameter endoscope with an endoscope
body provided with an endoscope insertion part insertion means that allows insertion
of an endoscope insertion part for capturing images into the interior of a root canal
or a periodontal pocket with a simplified, easy operation, to improve operability
of introducing the endoscope insertion part into the interiors of the root canal and
the periodontal pocket. The extremely small diameter endoscope has a function of preventing
damages to the endoscope insertion part while it is not being introduced into the
root canal or the periodontal pocket.
Means for Solving the Problems
[0008] According to a major aspect of the present invention, an extremely small diameter
endoscope includes: an endoscope body having a distal end nozzle; an imaging unit
disposed in the endoscope body and adapted for capturing an image; an endoscope insertion
part comprising a proximal end portion and a projection end portion, the proximal
end portion connected to the imaging unit, the endoscope insertion part passing through
the distal end nozzle, the projection end portion to be positioned in a root canal
of a tooth or in a periodontal pocket; and endoscope insertion part insertion means
adapted for inserting the endoscope insertion part into an observation portion in
the root canal of the tooth or in the periodontal pocket with an end portion of the
distal end nozzle kept abutted against a surrounding portion of the observation portion.
Advantageous Effects of the Invention
[0009] The invention according to claim 1 provides an extremely small diameter endoscope
that allows, by the endoscope insertion part insertion means, bringing the end portion
of the distal end nozzle into abutment with the surrounding portion of the observation
portion in the root canal of the tooth or in the periodontal pocket and inserting
the endoscope insertion part into the observation portion, and thereby allows capturing
an image of the interior, including blind spots thereof, of the root canal or the
periodontal pocket while improving operability in introducing the endoscope insertion
part into the root canal or the periodontal pocket and allows preventing damages to
the endoscope insertion part while it is not being introduced into the root canal
or the periodontal pocket.
[0010] According to the invention of claim 2, the endoscope insertion part insertion means
allows for moving the endoscope insertion part in the endoscope body and the distal
end nozzle in conjunction with the imaging unit that is moved forward and backward
by an operation of a lever slidably attached to the endoscope body. This structure
makes it possible for the extremely small diameter endoscope to capture an image of
the interior, including blind spots thereof, of the root canal or the periodontal
pocket while improving operability in introducing the endoscope insertion part into
the root canal or the periodontal pocket and prevent the endoscope insertion part
from being damaged while it is not being introduced into the root canal or the periodontal
pocket.
[0011] According to the invention of claim 3, in the extremely small diameter endoscope
described in claim 1 or 2, the distal end nozzle is made of a hard material and the
endoscope insertion part has a mantle made of a flexible, elastic material. With this
structure of the extremely small diameter endoscope, the endoscope insertion part
insertion means can be operated to introduce/withdraw the endoscope insertion part
into/from the interior of the root canal or the periodontal pocket with good operability.
[0012] According to the invention of claim 4, in the extremely small diameter endoscope
described in any one of claims 1 to 3, the distal end nozzle has a projection end
portion at which an ingress/egress guiding abutment piece is formed in a substantially
spoon-like shape or a substantially scoop-like shape, and the distal end nozzle is
adapted to allow the endoscope insertion part to be moved along an inner surface of
the ingress/egress guiding abutment piece. With this structure of the extremely small
diameter endoscope, the endoscope insertion part can be smoothly introduced into or
withdrawn from the interior of the root canal or the periodontal pocket while moving
the endoscope insertion part with good operability.
[0013] According to the invention of claim 5, in the extremely small diameter endoscope
described in claim 4, the distal end nozzle including the ingress/egress guiding abutment
piece is curved in a shape suitable for observation. With this structure of the extremely
small diameter endoscope, the endoscope insertion part can be introduced into or withdrawn
from the interior of the root canal or the periodontal pocket with good operability
in a state where the endoscope insertion part fits the shape of the root canal or
the periodontal pocket.
[0014] According to the invention of claim 6, in the extremely small diameter endoscope
described in any one of claims 1 to 5, the extremely small diameter endoscope further
includes a distal end nozzle holding sleeve that holds the distal end nozzle on the
endoscope body. The distal end nozzle holding sleeve is configured to be attachable
to and detachable from the endoscope body. With this structure of the extremely small
diameter endoscope, the distal end nozzle can be simply and easily replaced by detaching
and attaching the distal end nozzle holding sleeve.
[0015] According to the invention of claim 7, the distal end nozzle has an expansion-contraction
structure such that: the distal end nozzle shrinks or moves to increase an amount
of projection of an end portion of the endoscope insertion part from an end portion
of the distal end nozzle by bringing the end portion of the distal end nozzle into
abutment with a surrounding region of an entrance to the root canal or the periodontal
pocket; and the projection is eliminated by causing the end portion of the distal
end nozzle to expand by releasing the abutment of the end portion of the distal end
nozzle with the surrounding region of the entrance to the root canal or the periodontal
pocket. This structure of the extremely small diameter endoscope allows capturing
an image of the interior, including blind spots thereof, of the root canal or the
periodontal pocket while improving operability in introducing the endoscope insertion
part into the root canal or the periodontal pocket and preventing damage to the endoscope
insertion part while it is not being introduced into the root canal or the periodontal
pocket.
[0016] According to the invention of claim 8, the distal end nozzle includes an expansion-contraction
member that constitutes a part or the whole of the distal end nozzle. Bringing the
distal end nozzle into abutment with the surrounding region of the entrance to the
root canal or the periodontal pocket causes the expansion-contraction member to shrink
and thus causes the endoscope insertion part to come out from the distal end nozzle;
and releasing the abutment between the distal end nozzle and the surrounding region
of the entrance to the root canal or the periodontal pocket causes the expansion-contraction
member to expand and thus causes the endoscope insertion part to be housed in the
distal end nozzle. This structure makes it possible for the extremely small diameter
endoscope to capture an image of the interior, including blind spots thereof, of the
root canal or the periodontal pocket while improving operability in introducing the
endoscope insertion part into the root canal or the periodontal pocket and prevent
the endoscope insertion part from being damaged while it is not being introduced into
the root canal or the periodontal pocket.
[0017] The invention of claim 9 can provides an extremely small diameter endoscope that
provides the same advantageous effects as those of the invention of claim 1 and allows
capturing a high-quality, high-brightness image of the root canal or the periodontal
pocket.
[0018] According to the invention of claim 10, in the extremely small diameter endoscope
described in any one of claims 1 to 9, a general purpose channel with a hollow structure
is provided in the endoscope insertion part. This structure of the extremely small
diameter endoscope makes it possible to inject lavage fluid and/or drug into an affected
part in the interior of the root canal or the periodontal pocket using the general
purpose channel, and further provide treatment by irradiating the affected part with
laser by inserting a laser fiber into the general purpose channel.
Brief Description of the Drawings
[0019]
FIG. 1 is an external perspective view of an extremely small diameter endoscope according
to an embodiment of the present invention.
FIG. 2 shows a cross section of the extremely small diameter endoscope (positioned
at an imaging unit retreat position) according to the present embodiment and shows
the form of an endoscope insertion part and an imaging unit at this position.
FIG. 3 shows a cross section of the extremely small diameter endoscope (positioned
at an imaging unit advance position) and shows the form of the endoscope insertion
part and the imaging unit at this position.
FIG. 4 is an explanatory view of the extremely small diameter endoscope according
to the present embodiment, showing the form of the extremely small diameter endoscope
when capturing an image of a root canal.
FIG. 5 is an external perspective view of an extremely small diameter endoscope according
to a modification of the present embodiment.
FIG. 6 is an explanatory view of the extremely small diameter endoscope according
to the modification of the present embodiment, showing the form of the extremely small
diameter endoscope when capturing an image of a root canal.
FIG. 7 is a schematic cross-sectional view of the extremely small diameter endoscope
according to the modification, showing another expansion-contraction structure of
a distal end nozzle of the extremely small diameter endoscope.
FIG. 8 is a schematic cross-sectional view of an extremely small diameter endoscope
according to another modification of the present embodiment.
FIG. 9 is a schematic explanatory view of an extremely small diameter endoscope employing
a distal end nozzle with an ingress/egress guiding abutment piece of the present embodiment,
showing the form of the extremely small diameter endoscope when capturing an image
in the interior of a periodontal pocket.
FIG. 10 is a partial perspective view of a distal end nozzle with a straight ingress/egress
guiding abutment piece according to the present embodiment as well as the endoscope
insertion part.
FIG. 11 is a partial perspective view of three modifications of the ingress/egress
guiding abutment piece according to the present embodiment.
FIG. 12 is a cross-sectional view of an end of another configuration of the endoscope
insertion part arranged in the distal end nozzle of the present embodiment.
FIG. 13 is a cross-sectional view of an end of yet another configuration of the endoscope
insertion part of the present embodiment.
FIG. 14 is an external perspective view of an extremely small diameter endoscope according
to another embodiment of the present invention.
FIG. 15 is a schematic cross-sectional view of an extremely small diameter endoscope
(positioned at a lever retreat position) according to another embodiment and a diagram
showing the form of the endoscope insertion part and the image processing unit at
that position.
Embodiments of Invention
[0020] In order to achieve the purpose of providing an extremely small diameter endoscope
having improved operability of introducing an endoscope insertion part into a root
canal or a periodontal pocket and having a function of preventing damage to the endoscope
insertion part while it is not being introduced into the root canal or the periodontal
pocket, the present invention provides an extremely small diameter endoscope including:
an endoscope body having a distal end nozzle; an imaging unit disposed in the endoscope
body and adapted for capturing an image; an endoscope insertion part comprising a
proximal end portion and a projection end portion, the proximal end portion connected
to the imaging unit, the endoscope insertion part passing through the distal end nozzle,
the projection end portion to be positioned in a root canal of a tooth or in a periodontal
pocket; and endoscope insertion part insertion means adapted for inserting the endoscope
insertion part into an observation portion in the root canal of the tooth or in the
periodontal pocket with an end portion of the distal end nozzle kept abutted against
a surrounding portion of the observation portion, wherein the endoscope insertion
part insertion means includes a lever slidably attached to the endoscope body and
allows moving the endoscope insertion part in the endoscope body and in the distal
end nozzle in conjunction with the imaging unit that is moved forward and backward
in the endoscope body by an operation of the lever.
Embodiment
[0021] Hereinafter, an extremely small diameter endoscope according to an embodiment of
the present invention will be described in detail with reference to the drawings.
[0022] As shown in FIGS. 1 to 4, the extremely small diameter endoscope according to the
present embodiment has: a distal end nozzle holding sleeve 3 on a distal end side;
a cylindrical endoscope body 2 that holds a proximal end portion of a thin, elongated
cylindrical distal end nozzle 11 with this distal end nozzle holding sleeve 3, through
which distal end nozzle 11 a later-mentioned endoscope insertion part 12 is inserted;
an imaging unit 4 arranged in the endoscope body 2 and equipped with an image pickup
part 4A, such as a CCD camera module, configured to capture an image of a root canal
or a periodontal pocket; an endoscope insertion part 12 having a proximal end portion
connected to the imaging unit 4 in the endoscope body 2 and a projection end 12a which
is positioned, for example, in a root canal 22 of a later-described tooth 21 when
the endoscope insertion part 12 is made to pass through the distal end nozzle holding
sleeve 3 and the distal end nozzle 11 in such a way that the projection end 12a comes
out forward from a distal end aperture 11b of the distal end nozzle 11; and endoscope
insertion part insertion means 6 for bringing an end portion of the distal end nozzle
11 provided on the endoscope body 2 into abutment with a surrounding region (surrounding
end surface) of an entrance to the root canal 22 (or an entrance to the later-mentioned
periodontal pocket) and inserting the endoscope insertion part 12 into the root canal
22 or the like.
[0023] The distal end nozzle holding sleeve 3 is configured to be attachable to and detachable
from the endoscope body 2, for example, with a thread engagement structure so that
the distal end nozzle 11 can be easily replaced.
[0024] In other words, when the distal end nozzle holding sleeve 3 is detached from the
endoscope body 2, the distal end nozzle 11 and the distal end nozzle holding sleeve
3 can be drawn out from the endoscope insertion part 12 and then the distal end nozzle
11 can be replaced with another one.
[0025] By inserting a freely selected distal end nozzle 11 over the endoscope insertion
part 12 and threadedly engaging the distal end nozzle holding sleeve 3 with the endoscope
body 2, the distal end nozzle 11 can be fixed in a freely selected orientation by
a pressing force from the inner side of the distal end nozzle holding sleeve 3.
[0026] Incidentally, the distal end nozzle 11 can be formed integrally with the distal end
nozzle holding sleeve 3 and the distal end nozzle holding sleeve 3 can be configured
to be replaceable.
[0027] The distal end nozzle 11 is formed of a hollow structure using, for example, a material
that is strong and less deformable. According to the embodiment, the distal end nozzle
11 is made of a metal material, but is not limited thereto.
[0028] The endoscope insertion part 12 has a mantle (corresponding to the guide tube 31
shown in FIG. 12) formed of, for example, an elastic flexible material that can be
curved. According to the embodiment, the mantle is made of a metal material but it
is not limited thereto. In the present case, for example, an imaging element including
a combination of a lens and a CCD element may be arranged at a distal end of the interior
of the endoscope insertion part 12. In this case, the imaging unit 4 is equipped with
only an image processing circuit.
[0029] The endoscope insertion part insertion means 6 includes the imaging unit 4 and has
a coupling projection 5a coupled to a peripheral portion of the imaging unit 4, attached
to a peripheral portion of the endoscope body 2, and inserted through an elongated
hole 2a formed on the endoscope body 2. The endoscope insertion part insertion means
6 further has a lever 5 for, by a sliding operation with a finger, advancing and retreating
the endoscope insertion part 12, and, at the same time, advancing and retreating the
imaging unit 4 in the endoscope body 2 between a retreat position shown in FIG. 2(a)
and an advance position shown in FIG. 3(a) (a position such that the distal end portion
of the endoscope insertion part 12 does not project from a distal end aperture 11b
of the distal end nozzle 11).
[0030] FIG. 2(b) shows the form of the endoscope insertion part 12 and the imaging unit
4 at the retreat position of the lever 5, and FIG. 3(b) shows the form of the endoscope
insertion part 12 and the imaging unit 4 at the advance position of the lever 5.
[0031] The endoscope insertion part insertion means 6 is configured move the endoscope insertion
part 12 in the endoscope body 2, the distal end nozzle holding sleeve 3, and the distal
end nozzle 11 in conjunction with the advancing or retreating movement of the imaging
unit 4 and further to cause the distal end portion of the endoscope insertion part
12 to come out from and return into an end of the distal end aperture 11b of the distal
end nozzle 11.
[0032] Incidentally, a root canal image captured by the imaging unit 4 is transmitted via
a not-shown signal transmission cable to an image display means to be rendered as
an image thereon for observation. Detailed description of this aspect is omitted.
[0033] Next, a description will be given of how the extremely small diameter endoscope 1
according to the present embodiment captures an image in the root canal 22 of the
tooth 21 with reference to FIG. 4.
[0034] To capture an image of the interior of the root canal 22 of the tooth 21 by the extremely
small diameter endoscope 1 according to the present embodiment, first, the lever 5
provided on the extremely small diameter endoscope 1 is brought to the retreat position
and the distal end portion of the endoscope insertion part 12 is brought to an end
surface of the distal end aperture 11b of the distal end nozzle 11, and then, as shown
in the upper half of FIG. 4, the end surface of the distal end aperture 11b of the
distal end nozzle 11 is brought into abutment with a surrounding end surface of an
entrance to the root canal 22.
[0035] Next, as shown in the lower half of FIG. 4, the lever 5 is operated to move the endoscope
insertion part 12 to an advance position.
[0036] In this way, the distal end portion of the endoscope insertion part 12 enters the
interior of the root canal 22 in conjunction with the operation of the lever 5.
[0037] The depth to which the distal end portion of the endoscope insertion part 12 penetrates
into the interior of the root canal 22 can be controlled by controlling the operation
amount of the lever 5.
[0038] In this way, it is possible to cause the distal end portion of the endoscope insertion
part 12 to reach a desired position in the root canal 22 with a very simple operation
with good operability, and observe and capture an image of the vicinity, including
blind spots thereof, of the desired position.
[0039] When the lever 5 is brought back to the original position, the distal end portion
of the endoscope insertion part 12 is at the end surface of the distal end aperture
11b of the distal end nozzle 11, i.e., the projection of the distal end portion from
the end surface of the distal end aperture 11b of the distal end nozzle 11 disappears.
[0040] With this operation, it is possible to avoid such an undesirable situation that,
when the distal end nozzle 11 is brought into or out of the oral cavity, the endoscope
insertion part 12 (in particular, the distal end portion of the endoscope insertion
part 12) comes into contact with another tooth or the like and is broken.
[0041] Next, an extremely small diameter endoscope 1A according to a modification of the
present embodiment will be described in detail with reference to FIGS. 5 and 6.
[0042] The basic structure of the extremely small diameter endoscope 1A according to the
modification is substantially the same as that of the extremely small diameter endoscope
1 of the embodiment. However, the extremely small diameter endoscope 1A adopts an
endoscope body 2 with the lever 5 being omitted, and, in place of the endoscope insertion
part insertion means 6, has an endoscope insertion part insertion means 6A having
a distal end nozzle 11A a part or the whole of which is an expansion-contraction structure
formed of, for example, an elastic rubber material in an elongated circular tube shape.
The distal end nozzle 11A houses the endoscope insertion part 12 in such a way that
the endoscope insertion part 12 can come out from and return into a distal end aperture
11b.
[0043] When capturing an image of the interior of the root canal 22 of the tooth 21, as
shown in FIG. 6, an end portion of the distal end nozzle 11A is brought into contact
with (brought into abutment with) a surrounding region of an entrance to the root
canal 22 to shrink the end portion so as to increase the amount of projection of the
endoscope insertion part 12 from the end portion of the distal end nozzle 11A into
the root canal 22. Then, the projection of the endoscope insertion part 12 is eliminated
by causing the end portion of the distal end nozzle 11A to expand due to its elastic
force by releasing the abutment of the end portion of the distal end nozzle 11A with
the surrounding region of the entrance to the root canal 22.
[0044] In other words, bringing the distal end nozzle 11A into abutment with the surrounding
end surface of the entrance to the root canal 22 causes a part or the whole of the
distal end nozzle 11a to shrink and thus causes the endoscope insertion part 12 to
come out from the distal end nozzle 11A, and releasing the abutment between the distal
end nozzle 11A and the surrounding end surface of the entrance to the root canal 22
causes the part or the whole of the distal end nozzle 11a to expand and thus causes
the endoscope insertion part 12 to be housed in the distal end nozzle 11A.
[0045] Incidentally, in the embodiment shown in FIG. 6, only the distal end portion of the
distal end nozzle 11A is shrunken. However, of course, the distal end nozzle 11A may
be configured to entirely shrink.
[0046] The amount of insertion of the distal end portion of the endoscope insertion part
12 into the root canal 22 can be varied by controlling the abutment force of the end
portion of the distal end nozzle 11A applied to the surrounding region of the entrance
to the root canal 22.
[0047] Even with the extremely small diameter endoscope 1A according to the modification,
the distal end portion of the endoscope insertion part 12 can be made to reach a desired
position in the root canal 22 with a very simple operation with good operability,
and an image can be captured from that position to be observed.
[0048] In addition, it is possible to avoid such an undesirable situation that, when the
distal end nozzle 11 is brought into or out of the oral cavity, the endoscope insertion
part 12 (in particular, the distal end portion of the endoscope insertion part 12)
comes into contact with another tooth and is broken.
[0049] FIG. 7 shows a distal end nozzle 11C adopted in place of the distal end nozzle 11A
in the extremely small diameter endoscope 1A according to the modification.
[0050] This distal end nozzle 11C has: a proximal end portion 16 having a circular cylindrical
shape and arranged in the distal end nozzle holding sleeve 3; and a projection nozzle
17 with an elongated, circular tube shape. This distal end nozzle 11C allows the endoscope
insertion part 12 connected with the imaging unit 4 to be inserted through the proximal
end portion 16 and the projection nozzle 17. The proximal end portion 16 is provided
with an expansion-contraction part 18 formed in a coil shape using, for example, a
metal material or synthetic resin material.
[0051] Even with the extremely small diameter endoscope 1A adopting such a distal end nozzle
11C, utilizing the expansion and contraction of the expansion-contraction part 18,
the distal end portion of the endoscope insertion part 12 can be made to reach a desired
position in the root canal 22 with a very simple operation with good operability in
the same manner as that shown in FIG. 6 and an image can be captured from that position
to be observed. Moreover, it is possible to avoid such an undesirable situation that,
when the distal end nozzle 11C is brought into or out of the oral cavity, the endoscope
insertion part 12 (in particular, the distal end portion of the endoscope insertion
part 12) comes into contact with another tooth and is broken.
[0052] Next, an extremely small diameter endoscope 1B according to another modification
of the present embodiment will be described in detail with reference to FIG. 8.
[0053] The basic structure of the extremely small diameter endoscope 1B according to the
another modification is substantially the same as that of the extremely small diameter
endoscope 1 of the embodiment. However, the extremely small diameter endoscope 1B
is characterized in further including an illumination light guide 15 with a linear
shape. The illumination light guide 15 guides illumination light emitted from a light
source part 14 made up of a light-emitting diode or the like and provided along the
image pickup part 4A in the imaging unit 4, and emits the illumination light toward
the interior of the root canal 22 of the tooth 21 from a position adjacent to the
distal end of the endoscope insertion part 12.
[0054] As a matter of course, any one of the distal end nozzle 11A and the distal end nozzle
11C can be adopted even in this root canal imaging instrument 1B.
[0055] The extremely small diameter endoscope 1B according to the another modification even
can provide the same effects as those of the above-described extremely small diameter
endoscopes 1 and 1A and allows capturing a more bright, high quality image of a root
canal by emitting the illumination light from the illumination light guide 15 toward
the interior of the root canal 22.
[0056] Next, a description will be given of a distal end nozzle 11D that allows the extremely
small diameter endoscope 1 of the above-described embodiment to have a function of
capturing an image of a periodontal pocket 24 between a gum 23 and a tooth 21, with
reference to FIGS. 9, 10 and 11.
[0057] The distal end nozzle 11D has a structure substantially the same as the above-described
distal end nozzle 11. However, the distal end nozzle 11D is characterized in including
a distal end portion at which a straight ingress/egress guiding abutment piece 11e
for the projection end 12a of the endoscope insertion part 12 is formed.
[0058] The ingress/egress guiding abutment piece 11e includes an abutment portion 11j for
abutting on a periphery region of an opening of the periodontal pocket 24. The abutment
portion 11j is a projection end of the distal end nozzle 11D, which projection end
is formed by processing the hollow distal end nozzle 11D so as to have a distal end
portion substantially having an external shape of a scoop.
[0059] That is, the ingress/egress guiding abutment piece 11e guides the projection end
12a of the endoscope insertion part 12 in such a way that, when the state of the projection
end 12a of the endoscope insertion part 12 is changed from a state, shown in FIG.
10(a), where the projection end 12a of the endoscope insertion part 12 is at a position
corresponding to when the lever 5 of the endoscope insertion part insertion means
6 is at the retreat position, to a state, shown in FIG. 10(b), where the lever 5 has
been operated to move to a position corresponding to an advance position (where the
projection end 12a projects further than the abutment portion 11j in an outward direction),
the projection end 12a and a part of a portion of the endoscope insertion part 12
that succeeds the projection end 12a (front side in FIG. 10) are exposed to the outside
and the other part of the endoscope insertion part 12 (back side in FIG. 10) is in
contact with an inner periphery surface of the ingress/egress guiding abutment piece
11e.
[0060] With the extremely small diameter endoscope 1 provided with the distal end nozzle
11D having such a structure, as shown in FIG. 9, it is possible to capture an image
of the interior of the periodontal pocket 24 with good operability by inserting the
abutment portion 11j into the periodontal pocket 24 in such a way that a space is
created in the periodontal pocket 24 and the abutment portion 11j, bringing the abutment
portion 11j into abutment with a periphery portion of an observation portion, and
operating the lever 5 to move to an advance position so that the projection end 12a
of the endoscope insertion part 12 reaches a desired position in the periodontal pocket
24.
[0061] In addition, it is possible to avoid such an undesirable situation that, when the
distal end nozzle 11D is brought into or out of the oral cavity, the endoscope insertion
part 12 (in particular, the projection end 12a of the endoscope insertion part 12)
comes into contact with another tooth and is broken.
[0062] FIG. 11 illustrates three embodiments of the modification of the distal end nozzle
11D. FIG. 11(a) shows a curved ingress/egress guiding abutment piece 11f which can
be a replacement for the ingress/egress guiding abutment piece 11 e. The curved ingress/egress
guiding abutment piece 11f has a distal end portion whose external shape is substantially
scoop-shaped and is curved. FIG. 11(b) shows a curved ingress/egress guiding abutment
piece 11g which can be a replacement for the ingress/egress guiding abutment piece
11e. The curved ingress/egress guiding abutment piece 11g has a distal end portion
at which a spoon-shaped bulge 11i is formed and the external shape of which is substantially
spoon-shaped and is curved. FIG. 11(c) shows a straight ingress/egress guiding abutment
piece 11h which can be a replacement for the ingress/egress guiding abutment piece
11e. The straight ingress/egress guiding abutment piece 11h has a distal end portion
at which a spoon-shaped bulge 11i is formed and the external shape of which is substantially
spoon-like and is straight.
[0063] Even with an extremely small diameter endoscope 1 equipped with the distal end nozzle
11D with any one of the curved ingress/egress guiding abutment piece 11f, the curved
ingress/egress guiding abutment piece 11g, and the straight ingress/egress guiding
abutment piece 11h, it is possible to provide the same operations and advantageous
effects as those provided by the extremely small diameter endoscope 1 equipped with
the distal end nozzle 11D having the above-described configuration shown in FIG. 10.
In addition, it is further possible to select a distal end nozzle 11D depending on
different shapes of the openings of various periodontal pockets 24, to capture an
image of a periodontal pocket. It should be noted that each distal end nozzle 11D
can be easily exchanged by attaching/detaching the distal end nozzle holding sleeve
3 to/from the endoscope body 2.
[0064] Next, another configuration of the endoscope insertion part 12 will be described
with reference to FIGS. 12 and 13.
[0065] FIG. 12 shows the configuration of a distal end surface of the distal end nozzle
11, in a hollow portion of which an endoscope insertion part 12B is movably arranged.
[0066] The endoscope insertion part 12B includes: a guide tube (mantle, e.g., electroformed
tube) 31 slidably in contact with an inner circumference of the hollow portion of
the distal end nozzle 11 and having flexibility; a light guide 33 having a circular
cylindrical shape and arranged in the guide tube 31 with an outer circumference of
the light guide 33 being in contact with an inner circumference of the guide tube
31; and an image guide 32 arranged concentrically with a central portion of this light
guide 33 to penetrate therethrough.
[0067] The above-described guide tube 31 is made of an elastic material that can be curved.
In the another configuration example illustrated in FIG. 12, the guide tube 31 is
formed of a thin metal material, but it is not limited thereto.
[0068] When an endoscope insertion part 12B having such a configuration is adopted, it is
possible to provide the same operations and advantageous effects as those described
above for the extremely small diameter endoscope 1B shown in FIG. 8.
[0069] Although not illustrated, the endoscope insertion part 12B shown in FIG. 12 may be
configured to include, in place of the image guide 32, an extremely small camera,
such as a CCD module or the like, and a signal transmission cable. In this case, an
image processing unit is used in place of the imaging unit 4 in the endoscope body
2.
[0070] The guide tube 31 serves as a guide for protecting the image guide 32 and further
the extremely small camera and the signal transmission cable, and for guiding them
to an affected part.
[0071] FIG. 13 illustrates an endoscope insertion part 12C having a different configuration
from that of the endoscope insertion part 12B. The endoscope insertion part 12C includes:
a guide tube (mantle) 31 slidably in contact with an inner circumference of the hollow
portion of the distal end nozzle 11 and having flexibility; a light guide 34 arranged
in the guide tube 31 with an outer circumference of the light guide 34 being in contact
with an inner circumference of the guide tube 31; an image guide 32 disposed to penetrate
through the light guide 34; and a general purpose channel (hollow hole) 35 disposed
to penetrate through the light guide 34 separately from the image guide 32.
[0072] When the endoscope insertion part 12C thus structured is adopted, it is possible
to provide the same operations and advantageous effects as those described above for
the extremely small diameter endoscope 1B shown in FIG. 8. In addition, as the endoscope
insertion part 12C has the general purpose channel 35, it is possible to inject lavage
fluid and/or drug into an affected part using the general purpose channel 35 and further
treat the affected part with laser irradiation by, although not illustrated, inserting
a laser fiber into the general purpose channel 35.
[0073] Next, a description will be given of an extremely small diameter endoscope 1C according
to another embodiment of the present invention with reference to FIGS. 14, 15(a) and
15(b).
[0074] As to the extremely small diameter endoscope 1C according to another embodiment,
the same elements as in the case of the extremely small diameter endoscope 1 shown
in FIG. 1 are given the same reference signs, and their detailed description will
be omitted.
[0075] The basic structure of the extremely small diameter endoscope 1C according to the
another embodiment is substantially the same as that of the extremely small diameter
endoscope 1 of the embodiment. However, the extremely small diameter endoscope 1C
is characterized in that an image processing unit 41 with an image processing circuit
41a is disposed in the endoscope body 2 in place of the imaging unit 4, an endoscope
insertion part 42 made up of: a flexible signal transmission cable 43 which has an
end portion located in the endoscope body 2 and connected to the image processing
unit 41; and an ultra-small size imaging element 44 disposed on a distal end of the
signal transmission cable 43 is adopted in place of the endoscope insertion part 12,
and the endoscope insertion part insertion means 6 is operated to move the endoscope
insertion part 42 in the distal end nozzle 11 in conjunction with the image processing
unit 41, so that the ultra-small size imaging element 44 comes out from and returns
into the distal end aperture 11b.
[0076] Examples of the ultra-small size imaging element 44 include ultra-small size CCD
elements and ultra-small size C-MOS elements.
[0077] It should be noted that FIGS. 15(a) and 15(b) illustrate a state where the lever
5 of the endoscope insertion part insertion means 6 is at the retreat position.
[0078] The extremely small diameter endoscope 1C according to the another embodiment even
can provide the same operations and advantageous effects as those described above
for the extremely small diameter endoscope 1.
[0079] It should be noted that the extremely small diameter endoscope 1 shown in FIG. 1
and the like, the extremely small diameter endoscope 1A shown in FIG. 5 and the like,
the extremely small diameter endoscope 1B shown in FIG. 8 and the like, and the extremely
small diameter endoscope 1C shown in FIG. 14 and the like can be used for capturing
an image of the interior of a periodontal pocket 24 in addition to capturing an image
of the interior of a root canal 22. In addition, an extremely small diameter endoscope
1 using a distal end nozzle 11D provided with any one of the ingress/egress guiding
abutment pieces 11e to 11h can be used for capturing an image of the interior of a
root canal 22 in addition to capturing an image of the interior of a periodontal pocket
24.
Industrial Applicability
[0080] The present invention is applicable to capturing an image of the interior of a root
canal and the interior of a periodontal pocket 24 and further to capturing an image
of a treatment part having an affected part in a hole, and thus can be widely used
in the medical field.
Reference Signs List
[0081]
1 extremely small diameter endoscope
1A extremely small diameter endoscope
1B extremely small diameter endoscope
1C extremely small diameter endoscope
2 endoscope body
2a elongated hole
3 distal end nozzle holding sleeve
4 imaging unit
4A imaging pickup part
5 lever
5a coupling projection
6 endoscope insertion part insertion means
6A endoscope insertion part insertion means
11 distal end nozzle
11A distal end nozzle
11b distal end aperture
11C distal end nozzle
11D distal end nozzle
11e ingress/egress guiding abutment piece
11f curved ingress/egress guiding abutment piece
11g curved ingress/egress guiding abutment piece
11h straight curved ingress/egress guiding abutment piece
11i spoon-shaped bulge
11j abutment portion
12 endoscope insertion part
12a projection end
12B endoscope insertion part
12C endoscope insertion part
14 light source part
15 illumination light guide
16 proximal end portion
17 projection nozzle
18 expansion-contraction part
21 tooth
22 root canal
23 gum
24 periodontal pocket
31 guide tube
32 image guide
33 light guide
34 light guide
35 general purpose channel
41 image processing unit
41a image processing circuit
42 endoscope insertion part
43 signal transmission cable
44 ultra-small size imaging element